Steering mechanism for tractors



Aug. 23, 1932.

H; E. M CRAY STEERING MECHANISM FOR TRACTORS 2 Sheets-Sheet 1 FiledSept. 28, 1929 I INVENTOR- I HHHULD-E-M [SHAY WITNESS Aug. 23, 1932. H.E. MCCRAY 1,873,447

STEERING MECHANISM FOR TRACTORS Filed Sept. 28, 1929 2 heets-Sheet 2 V Lj INE/VTOR WITNESS I-ifiRmLn-E- BE Y MQM BY imnonn H of a tractorPatented Aug. 23, 1932 UNITED STATES'FPATETNITIOFFICE n. MCGRAY, onWATERLOO, IOWA, ASSIGNOR PANY, or WATERLOO, IOWA, A ooiaronA rfon OF,Iowa STEERING MECHANISM- FOR TRACTORS Application filed September 28,1929. Serial No. 395,856.

My invention relates to tractors and particularly to improvement of thesteering mechanism therefor and has for its object to increase thestrength of the members and to provide certain features of adjustment tocompensate for wear in the more active parts as fully described in thefollowing specification. Referring to the drawings in which simi larnumerals indicate identical parts Figure 1 is a plan view showingsuflicient to illustrate the application of my invention; Figure 2 is aof Figure 1; V

' Figure 3 is an enlarged detail of the steering gearing and connectedparts; and

Figure 4 is a section on the line Jr-4: of F i ure 3.

ufiicient of a tractor 1, of a well known has been shown in thedrawings, to illustrate my invention, and includes the housings 2 and 3in which the power mechanism of the vehicle is enclosed. As anentirety-the vehicle is supported on'traction wheels 4 and 5, shown inpart only, andforwardlyon steerable wheels one only, 6, beingillustrated and demonstrating the application of "certain parts of thesteering mechanism as will be hereinafter explained. Power to-actuatethe vehicle is derived from an engine, covered in the housing 2 and 3,shown only in part in detail section on the line 2-2 dotted lines, theengine including a crank shaft 7 dotted in Figure 1, operating suitablegearing to rotate the wheels 4 and V The steering. mechanism includes asteering wheel 8 mounted on a shaft 9 housed in a tubular member 10 thelower end of which is rigidly held in a collar 11. The collar 11 issplit for partvof its length so that by operation of a bolt firmlyclamped in position. The housing 13 is formed of parts a and b boltedtogether and mounted on the housing 3 and securely-held in place bybolts 14. The housing 3 is divided by a partition 15 into compartments16 and 17 the former housing the crank shaft 7 and the latter otherparts of the tractor mechanism. Adjacent the partition 15, and

forwardly thereof, is a tube 18 the upper end 12 the tubular member 10is of which is spread intov a through opening in an enlargement of thetop of the casing, and

the lower end is held in an enlargement of the bottom of the casing, thelower enlargement operating as a bearing for a perpendicular post 19.

On the upper endvof the post 19, which extends into the caslng part b'of the housing 13,

is a worm gear 20 meshing with a worm 21 on the forward end of the shaft9 and covered in the part a of said housing. On the lower end of thepost 19;is an arm 22 to which is pivotally connected a rod 23 extendingforwardly and pivotally attached to an arm- 24: of a horizontallydisposed crank connected to the wheel axle, the opposite arm 25 of thecrank is pivotally connected to an equalizer bar 26 pivotally fastenedto a similar arm on the opposite wheel mounting (not shown)v so thatboth front wheels are steered simultaneously as well known in the art.

The steering post 19 is perpendicular, as stated, and its upper end islessened in diameter to form a spindle 27 upon which the worm gear 20 issecured by a multiplespline tacts with a threaded bolt 29, as at 0,pro-" j ecting intothe housing I) through. a threaded orifice in anenlargement of the top of the housing;the bolt 29 operating ongthe upperendof the post to control any .upthrust of the post, the bolt beingadjustable so as to regulate the force of the contact. In mounting thepost 19 perpendicularly I amenabled to arrange the rod 23 in ahorizontal position and so avoid any cramping or binding upon the parts,to which it is connected, when steering the tractor over an unevensurface.

To Joan nnnnn'rimo'ron coM- It will be readily understood that byoperation of the steering wheel 8 the parts intervening between thewheel and the front wheels, and as described, are-actuated to steer thefront wheels in a well known manner, but I find that whenever thetractoris steered either to the right or left it is desirableto providesome means to regulate the degreeof angulation of the frontwheels sothat'the instances said means have been of such a na---- ture, and solocated, that rapid wear has refiliated it with the Worm gear of thesteering 1 mechanism and covered it in the housing 6.

sulted and their effectiveness materially lessened if not completelydestroyed. A's illustrated in Figures 2, 3 and 4 I have developed 3 avery'efiective device for limiting the angularity of the frontwheels'whenthe tractor is moving froma straight course and I haveafdevice consists'of a pin 30, a plurality of holes 34, 35 and 36 spacedapart in enlargements of the gear rim, equidistant and paral. lel withthe axis of the gear. Threaded bolts 3 32and 33 project into thehousing-through threaded openings in the wall thereof, and

L" opposite each other. As shown in Figures 3 and 4 the arts illustratedare in a cosition they assume when thejtractor is travel-' ing straightahead, the pin 31 being located I equidistant from the bolts 32 and 33when the hand wheel 8 is operated to steer the vehicle the limit oftheturn is decided I by the pin 31 contacting with either of the bolts32 and33 according to the direction inwhich the turn is made, the boltsbeing adjustable to increase or lessen the distance between them andconsequently ncrease or lessen the angularity of the front wheels.

In the event that the pin has become I damaged for any reason and it isdifficult to extract from the hole in the 'ear, in which it is held, itwill become necessary to insert a new pin in either. of the holes and36fand to accomplish this I dismount the housing a, carrying the Worm21, from the housing 5 so that the gear 20 will'be readily accessible;after r'otatingthe bolts 32 and 33 and the screw bolt 31 untilthey havereceded a sufficient distance, the nut 28 isremoved and the ge'ar raiseduntil it isfree of the spline 27 and readily removable' After a pin hasbeen inserted the gear is turned until the new pin 7 is in position, asshown, equidistant from the bolts 3'2and33. lie-engagement of the gearwith the spline 27 and replacement of the nut 28 again holds the gearsecurely on the post. The bolt 29 is lowered into contact with the postand the bolts 32 and 33 again adjustedv to limit the turn of the gear 20and consequently control'the angularity of the, front wheels whensteered. By again bolting the housing a to the housing bthe worm 21 andgear 20 are again in mesh ready for use.

In the operation just describedit is evident that different teeth, onthe worm gear 20 will be brought into mesh with the worm 21, providingnew surfaces ofcontaot'between the I bearing accumulated in operation ofthe tractor, and

this protection I assure by covering the post with atubulai'inemben'within which the postrotates, thesame time leakage of oil fromthe crank shaft housing at the lower of the'posti's prevented by theperv member with the bottom of the crank case. Y What I claim 7 '1. In atractor having a crank shaftand a housing therefor, the combinationtherewith of a perpendicular tubular member within said housing andsecured to the top and bottom of the housing, the connections therewithbcingoil tight, a rotatable post journaledin a bearing in the bottom ofthe housing and covered within said membenmeans connecting the lower endof saidpost with the front wheels of the tractor and actuable to steersaid wheels by rotary movement of the post, a gear housing detachablysecured on the crank shaft housing having a bearing in which the upperend of said post is j ournaled, a worm gear on the post within thehousing,

fect joint of the tubular aworm meshing with said gear andmanuallybottom thereof, a bearing in the bottom of said housing in which thelower end of said post is journaled, means connecting the lowerv end ofthepost with thefront wheels of the itractor and actuable to steer saidwheels by rotary movement of the post,a gear housing covering the upperen'd of the postand detachably fixed to said crank shaftrhousing,

a second I bearing in said gear housing in Wl'llCh the upper end ofsaidpost is ournaled,

a worm gear onthe end of the post within the I housing above said secondbearing, a shaft journaled in the housingover the worm. gear, a worm onsaid shaft meshing with said gear, and a wheel on the shaft manuallyoperable toturn the shaft and worm and gear and im-.

part rotary movement to the post to steer said wheels.' I

3. In atractor having a crankshaft and a housing therefor, thecombination therewith of a steering mechanismincluding a perpendicularrotatable post supported within the housing, means connecting said postwith the front wheels of the tractor and actuableto steerthe wheels byrotary movement of the "post, a gear housing covering the upper end ofthe post, a worm gear on the post within the gear housing, a shaftjournaled in the latter housing, a worm on said shaft meshing with saidgear, a manually controlled device on said shaft operable to turntheshaft and actuate the worm and gear to impart rotary motion to thepost to steer the wheels, means on the worm gear coactingwith means onits housing to limit the rotation of said post in either direction, athreaded boring in said gear housing in alinement with said post, and ascrew threaded in said boring and adapted to contact with the end ofsaid post to take the end thrust thereof.

HAROLD MoCRAY.

